Junior civil service minister Georges Tron is the subject of a preliminary investigation into charges of rape and sexual assault after two women alleged that he had attacked them between 2007 and 2010.

One said she was inspired to come forward after a hotel chambermaid in New York claimed she was sexually assaulted by International Monetary Fund chief Dominique Strauss-Kahn.

Mr Tron (53) is a member of President Nicolas Sarkozy's conservative UMP party.

A statement from prime minister Francois Fillon's office noted Mr Tron has denied the allegations and praised him for acting in the "general interest".

The two women, aged 34 and 36, once worked at the town hall of Draveil, south of Paris, where Mr Tron is mayor.

They told 'Le Parisien' newspaper that Mr Tron assaulted them behind locked doors at the town hall.

One of the women, who was not identified by name, said she was too ashamed to tell anyone at first, but she added: "When I saw that a chambermaid was capable of taking on Dominique Strauss-Kahn, I told myself I didn't have the right to keep quiet. Other women may be suffering what I suffered. I have to help them. We have to break this code of silence."

Mr Tron's lawyer, Olivier Schnerb, has said the allegations against him are "unjust" and he has received instructions from his client to sue the women for "malicious slander". He claims the women were both fired from their jobs at the town hall of Draveil, south of Paris -- where Mr Tron has been mayor since 1995.

The newsweekly 'L'Express' quoted Mr Tron as vowing in his letter of resignation to "make (his) innocence known by combatting the vindictive allegations of two former colleagues," one of whom he claimed was dismissed for allegedly pilfering funds in her care, the other for unfit behaviour.